DETAILED DESCRIPTION OF THE INVENTION

[0020] REFERRING TO FIG. 1, a non-woven batt 100 has a longitudinal dimension 102, a lateral dimension 104 and a transverse dimension 106. The non-woven batt 100 may include a blend of different types of fibers 108 having varying diameters and deniers, and fibers which are hollow, solid and crimped. Blending different types of fibers 108 creates dead air spaces which contribute to the resiliency of the convoluted multi-layer pad 500 of the present invention (See FIGS. 3, 4 and 5) and lends to the integrity of the non-woven batt 100.

[0021] The fibers 108 of the non-woven batt 100 can be synthetic fibers which are known in the art, for example polyester and polypropylene. In an alternative embodiment, the fibers 108 are substantially synthetic fibers having a melting point in the range of about 189°-206°C. (300°-330°F.). In the preferred embodiment, the fibers 108 are polyester fibers having a melting point substantially in the above specified range. However, other synthetic fibers known in the art also may be used, such as polypropylene, having melt ranges close to or below the above-specified range. Additionally, natural fibers such as camel, llama, wool, cashmere, or cotton can be incorporated with synthetic fibers to form the non-woven batt 100. Because natural fibers may tend to generate smoke when in contact with a heated cutter, the percentage of natural fiber incorporated into the non-woven batt 100 should be within a range which will not create an environmental or health hazard during a heated cutting operation.

[0022] The fibers 108 of the non-woven batt 100 can also be densified. Densified fibers as used herein refers to fibers having a weight to thickness ratio of at least 57 grams (2 ounces) per 3.8 centimeter (1.5 inch) thickness for a 30.5 square centimeter (1 square foot) area of batt.

[0023] The fibers 108 can be oriented substantially horizontally 108a along the longitudinal dimension 102 and traverse dimension 106 of the non-woven batt 100. In an alternative embodiment, the non-woven batt 100 can be comprised of horizontally oriented fibers 108a, and vertically oriented fibers 108b along the lateral dimension 104 of the non-woven batt 100. In the preferred embodiment, the non-woven batt 100 is formed from substantially vertically oriented fibers 108b, as vertically oriented fibers 108b have better convolution retention properties as compared to horizontally oriented fibers 108a, as discussed below.

[0024] The batt 100 can be formed using one of the several processes for converting a source of fiber into a non-woven batt 100, as is known in the art. The fibers 108 may receive an application of a resin to improve the structural integrity of the non-woven batt 100, or alternatively may incorporate a portion of low melting fibers which will melt to bond high melt fibers in the non-woven batt 100 on application of heat. The ends of the fibers 108 in non-woven batt 100 may be brushed to improve the entwining of individual fibers of one end into adjacent ends. Adjacent ends of fibers 108 may be of substantially the same height, or alternatively may have different heights in a repeating pattern. The structure and manufacture of a batt incorporating vertically oriented fibers is described in more detail in U.S. Pat. No. 5,702,801, the entire disclosure of which is incorporated herein by reference.

[0025] In the early stages of forming the non-woven batt 100 from the fibers 108, the non-woven batt 100 may have an initial thickness of up to about eighteen (18) inches. The fibers 108 are spray bonded together with an adhesive and then compressed by rolling the fibers 108 to form the non-woven batt 100, as is known in the art. In an alternative process, the fibers 108 are oven-baked together and then rolled and cooled to form the non-woven batt 100.

[0026] REFERRING TO FIG. 2, a foam layer 200 has a longitudinal dimension 202, a lateral dimension 204 and a transverse dimension 206. The foam layer 200 preferably is a cellular foam structure which is resilient along its dimensions 202, 204, 206. The foam layer 200 compresses when weight or a load is placed along its dimensions 202, 204, 206 and returns generally to its original state when the weight or load is removed. The structure of a foam layer having a convoluted surface is described in U.S.Pat. No. 5,317,768, the entire disclosure of which is incorporated herein by reference.

[0027] The lateral dinension 204 of the foam layer 200 can be as large or as small as desired. In an alternative embodiment, the lateral dimension 204 is in the range of one half to three ({fraction (1/2)}-3) inches. In another alternative embodiment, the lateral dimension 204 is in the range of one to one and one half (1-1{fraction (1/2)}) inches. In the preferred embodiment, the lateral dimension 204 of the foam layer 200 is approximately 1{fraction (1/4)} inches.

[0028] REFERRING TO FIG. 3, the process of forming non-woven batt 100 having convoluted surface 160 is generally accomplished by transporting the non-woven batt 100 along its longitudinal dimension 102 while compressing the non-woven batt 100 along its lateral-dimension 104. Concomitantly with compression, the non-woven batt 100 is cut transversly along its lateral dimension 104 to separate the non-woven batt 100 into an upper segment 120 and a lower segment 140 and to provide conforming convoluted surface 160 of the batt upper and lower segments 120, 140. The batt upper and lower segments 120, 140 each have an upper surface 122, 142 and a lower surface 132, 152, respectively. The convoluted surface 160 of the batt upper segment 120 is proximate to its lower surface 132. Conversely, the convoluted surface 160 of the batt lower segment 140 is proximate to its upper surface142. A process for forming a non-woven fiber pad having a convoluted surface is disclosed, for example, in the aforementioned in U.S. patent application Ser. No. ______, entitled Convoluted Surface Fiber Pad, having as co-inventor Steven Eugene Ogle (the same inventor here) and filed on or about Jul. 29, 1999, the entire disclosure of which is incorporated herein by reference.

[0029] REFERRING TO FIG. 4, similar to the general process of forming non-woven batt 100 having a convoluted surface 160, the process of forming foam layer 200 having a convoluted surface 260 is generally accomplished by transporting the foam layer 200 along its longitudinal dimension 202 while compressing the foam layer 200 along its lateral dimension 204. Concomitantly with compression, the foam layer 200 is cut transversly along its lateral dimension 204 to separate the foam layer 200 into an upper segment 220 and a lower segment 240 and to provide conforming convoluted surface 260 of the foam layer upper and lower segments 220, 240, respectively. The foam layer upper and lower segments 220, 240 each have an upper surface 222, 242 and a lower surface 232, 252, respectively. The convoluted surface 260 of the foam layer upper segment 220 is proximate to its lower surface 232. Conversely, the convoluted surface 260 of the foam layer lower segment 240 is proximate to its upper surface 242.

[0030] REFERRING TO FIGS. 3 and 5, the preferred embodiment for transporting the non-woven batt 100 along its longitudinal dimension 102 is accomplished by a conveyor belt (not shown), although it is to be understood that alternate embodiments are known in the art. Compression of the non-woven batt 100 along its lateral dimension 104 is preferably accomplished by a pair of drums 10, 12 having opposite rotational directions D, D′. As the conveyor belt introduces the non-woven batt 100 between the drums 10, 12, the drums 10, 12 draw the non-woven batt 100 to compression.

[0031] Drums 10, 12 each have a convoluted surface 20 with at least one raised pattern thereon. The raised pattern is generally a plurality of upstanding projections and depressions. Alternative embodiments of the raised pattern include a plurality of pegs 22, straight edges 24 or waved edges 26, although it is to be understood that alternative raised patterns are known in the art. The convoluted surface 20 of drum 10 should not intermesh or come in contact with the convoluted surface 20 of opposite drum 12 as the drums 10, 12 rotate. In an alternative embodiment, only one of the drums 10,12 has a convoluted surface 20 while the other of the drums 10, 12 does not have a convoluted surface 20 which operates to facilitate the drawing of the batt 100 through the drums 10, 12.

[0032] As the non-woven batt 100 is drawn into frictional engagement with drum 10 and drum 12, the convoluted surface 20 of either of drum 10 or drum 12 compresses the non-woven batt 100 along its lateral dimension 104 towards the opposite drum 12, 10, respectively. A cutting device 30, schematically shown as an X, is positioned generally parallel to and between drum 10 and drum 12, and along the lateral dimension 104 of non-woven batt 100 as the non-woven batt 100 is transported between the drums 10, 12. In the preferred embodiment, the cutting device 30 is positioned proximate the location along the longitudinal dimension 102 of the non-woven batt 100 generally where the convoluted surface 20 of drum 10 or drum ,12 compresses the non-woven batt 100.

[0033] As the non-woven batt 100 encounters the cutting device 30, the cutting device 30 cuts through the non-woven batt 100 transversely and along the lateral dimension 104 to separate non-woven batt 100 into an upper segment 120 and a lower segment 140, each segment 120, 140 having an upper surface 122, 142 and a lower surface 132, 152, respectively. The cutting device 30 cuts through the non-woven batt 100 at a point along its lateral dimension 104 either nearer to the upper surface 122 of the batt upper segment 120 or to the lower surface 152 of the batt lower segment 140, whichever surface 122 or 152 is in contact with the convoluted surface 20, thus creating convoluted surface 160 of non-woven batt 100.

[0034] REFERRING BACK TO FIG. 4, the preferred embodiment for convoluting the foam layer 200 is similar to the process for convoluting the non-woven batt 100. Transportation of the foam layer 200 along its longitudinal dimension 202 is accomplished with a conveyor belt (not shown), although it is to be understood that alternate embodiments are known in the art. Compression of the foam layer 202 along its lateral dimension 204 is preferably accomplished by a pair of drums 50, 52 having opposite rotational directions E, E′. As the conveyor belt introduces the foam layer 200 between drums 50, 52, the drums 50, 52 draw the foam layer 200 to compression. Drums 50, 52 each have a convoluted surface 20 with at least one raised pattern thereon which corresponds to the raised pattern of drums 10, 12. The convoluted surface 20 of drum 50 should not intermesh or come in contact with the convoluted surface 20 of opposite drum 52 as the drums 50, 52 rotate. In an alternative embodiment, only one of the drums 50,52 has a convoluted surface 20 while the other of the drums 50, 52 does not have a convoluted surface 20 which operates to facilitate the drawing of the foam layer 200 through the drums 50, 52.

[0035] As the foam layer 200 is drawn into frictional engagement with drum 50 and drum 52, the convoluted surface 20 of either drum 50 or drum 52 compresses the foam layer 200 along its lateral dimension 204 towards the opposite drum 52, 50, respectively. A cutting device 70, schematically shown as an Y, is positioned generally parallel to and between drum 50 and drum 52, and along the lateral dimension 204 of foam layer 200 as the foam layer 200 is transported between the drums 50, 52. In the preferred embodiment, the cutting device 70 is positioned proximate the location along the longitudinal dimension 202 of foam layer 200 where the convoluted surface 20 of drums 50,52 compresses the foam layer 200. As the foam layer 200 encounters the cutting device 70, the cutting device 70 cuts through the foam layer 200 transversely and along the lateral dimension 204 to separate foam layer 200 into an upper segment 220 and a lower segment 240, each segment 220, 240 having an upper surface 222, 242 and a lower surface 232, 252, respectively. The cutting device 70 cuts through the foam layer 200 at a point along its lateral dimension 204 either nearer to the upper surface 222 of the foam layer upper segment 220 or to the lower surface 252 of the foam layer lower segment 240, whichever upper 222 or 252 is in contact with the convoluted surface 20.

[0036] It will be understood by those in the art that the drums 10, 12 may be positioned closer to or further away from each other depending on lateral dimension 104 of the non-woven batt 100 to be convoluted. Similarly, the distance between drums 50, 52 may be positioned depending on the lateral dimension 204 of the foam layer 200 to be convoluted. In the preferred embodiment, the convoluted surface 20 of drum 10 does not come into contact with or intermesh with the convoluted surface 20 of drum 12 to prevent the cutting device 30 from cutting through the upper surface 122 of the batt upper segment 120 or the lower surface 152 of the batt lower segment 140. Similarly, in the process for convoluting the foam layer 200, the convoluted surface 20 of drum 50 does not come into contact with or intermesh with the convoluted surface 20 of drum 52 to prevent the cutting device 70 from cutting through the upper surface 222 of the foam upper segment 220 or the lower surface 252 of the foam lower segment 240.

[0037] The cutting devices 30, 70 can be heated cutters. In the preferred embodiment, cutting devices 30, 70 are hot wires. The heate cutters of cutting devices 30 and 70 can be heated above the melting point of the fibers 108 of the non-woven batt 100 and of the foam 200, respectively, in order to speed the cutting process. For polyester fibers of the non-woven batt 100, the cutting device 30 should be heated in the range of about 189°-206° C. (300°-330° F.). For non-woven batt 100 formed from synthetic fibers 108 having a low melting point, as the heated cutter 30 cuts through the non-woven batt 100, the lower surface 132 of the batt upper segment 120 and the upper surface 142 of the batt lower segment 140 are bonded as fibers 108 lose their original plastic memory and then reform as a skin during cooling.

[0038] REFERRING TO FIG. 6,7, and 8, convoluted surfaces 160, 260 of the non-woven batt 100 and foam layer 200, respectively, are generally comprised of projections 302 and depressions 402 having different patterns and configurations depending upon the convoluted surface 20 of the drums 10, 12, 50, 52. For example, a plurality of pegs 22 of drum convoluted surface 20 forms a plurality of peaks 304 and basins 404 on convoluted surfaces 160, 260 of non-woven batt 100 and foam layer 200. A plurality of straight edges 24 on the drum convoluted surface 20 forms ridges 306 and valleys 406 on convoluted surfaces 160, 260 of the non-woven fiber batt 100 and the foam layer 200. Waved ridges 308 and waved valleys 408 on convoluted surfaces 160, 260 of the fiber batt 100 and foam layer 200 are formed of waved ridges on the convoluted surface 20 of the drum.

[0039] REFERRING BACK TO FIG. 8, generally the process for forming a convoluted combination fiber and foam pad includes disposing the convoluted surface 160 of at least one of the batt upper and lower segments 120, 140 in a conforming relationship to the convoluted surface 260 of at least one of the foam layer upper and lower segments 220, 240 to form a multi-layer pad of a non-woven fiber batt and foam layer having conforming convoluted surfaces. The cohesive nature of the non-woven batt 100 and the foam layer 200 would provide sufficient bonding in some applications. In alternative embodiments, the conforming convoluted surfaces160, 260, of the batt 100 and fiber 200, respectively, could be bonded using various bonding agents known in the art.

[0040] The preferred embodiment for forming a multi-layer pad of a non-woven batt and foam layer having conforming convoluted surfaces is accomplished by aligning the pair of drums 10, 12 substantially above the pair of drums 50, 52 and convoluting the non-woven batt 100 and the foam layer 200, respectively, as discussed above. The raised pattern of convoluted surface 20 of drums 50, 52 corresponds to the raised pattern of convoluted surface 20 of drums 10, 12. Upon cutting and convoluting non-woven batt 100, the upper and lower segments 120, 140 of the non-woven batt 100 are transported in relatively opposite and substantially horizontal directions, the lower surface 132 of the batt upper segment 120 facing relatively downward and the upper surface 142 of the batt lower segment 140 facing relatively downward. Thus, the convoluted surface 160 of the batt upper and lower segments 120, 140 is facing relatively downward. In an alternative embodiment, a pair of counter rotating rollers 14, 16 located generally below drums 10, 12 assist in trasnsporting the segments 120, 140 of the non-woven batt 100 in relatively opposite and substantially horizontal directions. In another alternative embodiment, a conveyor belt (not shown) proximate the surfaces opposite the convoluted surface 160 further assists in trasporting the segments 120, 140 of the non-woven batt 100 in opposite and horizontal directions.

[0041] Similarly, upon convolution of the foam layer 200 as detailed above, the upper and lower segments 220, 240 of the foam layer 200 are transported in relatively opposite and substantially horizontal directions, the lower surface 232 of the foam layer upper segment 220 facing relatively upward and the upper surface 242 of the foam layer lower segment 140 also facing relatively upward, and the convoluted surface 260 of the foam layer upper and lower segments 220, 240 facing relatively upward. In an alternative embodiment, a pair of counter rotating rollers 54, 56 located generally above drums 50, 52 assist in transporting the segments 220, 240 of the foam layer 200 in opposite and substantially horizontal directions. In another alternative embodiment, a conveyor belt (not shown) proximate the surfaces opposite the convoluted surface 260 further assists in transporting the segments 220, 240 of the foam layer 200 in opposite and horizontal directions.

[0042] As the segments 120, 140 of the non-woven batt 100, and the segments 220, 240 of the foam layer 200, are transported in opposite and generally horizontal directions, the batt upper segment 120 and the foam upper segment 220 come together laterally. Similarly, the batt lower segment 140 and the foam lower segment 240 laterally come together. In an alternative embodiment, the distance between conveyor belts (not shown) proximate the non-convoluted surfaces of the non-woven batt 100 and foam layer 200 are adjusted to accomplish the lateral movement. The batt convoluted surface 160 and the foam layer convoluted surface 260 are aligned to provide the upstanding projections 302 of the batt convoluted surface 160 to conform with or project into the depressions 402 of the foam convoluted surface 260, and the depressions 402 of the batt convoluted surface 160 to conform with or project into the upstanding projections 302 of the foam convoluted surface 260. In the preferred embodiment, alignment of the convoluted surfaces 160, 260 is accomplished by controlling the rotational speeds of drums 10, 12 and of drums 50, 52, and adjusting the horizontal placement of the convoluted surfaces 160, 260 for proper alignment. In an alternative embodiment as shown in FIG. 3, the peaks 304 of the batt and foam convoluted surfaces 160, 260, conform with or project into the corresponding basins 404 of the convoluted surfaces 260, 160 of the batt and foam, respectively. In another alternative embodiment shown in FIG. 4, the ridges 306 of the batt convoluted surface 160 and the foam convoluted surface 260 conform with or project into the corresponding valleys 406 of the foam convoluted surface 260 and the batt convoluted surface 160, respectively. In a further alternative embodiment shown in FIG. 5, the waved ridges 308 of the batt and foam convoluted surfaces 160, 260 conform with or project into the corresponding waved valleys 408 of foam and batt convoluted surfaces 260, 160, respectively.

[0043] The convoluted surfaces 160, 260 of the batt 100 and foam layer 200 can be bonded together with a bonding agent. The bonding agent can be applied in various manners and stages throughout the process as is known in the art. In a preferred embodiment, an apparatus 18, 20 sprays a bonding agent on at least one of the convoluted surfaces 160, 260 proximate rollers 14, 16 or rollers 54, 56.

[0044] REFERRING TO FIGS. 6, 7, 8, the multi-layer pad of a non-woven batt and a foam layer having conforming convoluted surfaces is for use in mattresses and cushions for sofas, loveseats, chairs and other upholstery products. The multi-layer pad 500 has convoluted surfaces 160, 260 generally comprised of projections 302 and depressions 402 in different patterns and configurations depending upon the convoluted surface 20 of the drums 10, 12, and 50, 52. The convoluted surfaces 160, 260 remain integral with unconvoluted thin bases 162, 262 of the non-woven batt 100 and the foam layer 200, respectively, to retain stiffness for using the multi-layer pad 500 in items such as sofas, cushions and mattresses. For example, convoluted surface 160 and base 162 are formed from the same non-woven batt 100 and convoluted surface 260 and base 262 are formed from the same foam layer 200. The non-woven batt component 100 of the multi-layer pad 500 may be made of either substantially vertically oriented low melt fibers 108b or substantially horizontally oriented densified low melt fibers 108b. When the non-woven batt component 100 of the multi-layer pad 500 is made from vertically oriented fibers 108b, the projections 302 of convoluted surface 160 have a greater ability to retain their shape when cut by the heated cutter 30, as the vertical orientation of fibers 108b resists sloughing off portions of the projections 302 during the convolution process.

[0045] In an alternative embodiment, projections 302 of the convoluted surfaces 160, 260 extend in the range of approximately one half to one ({fraction (1/2)}-1) inch in a lateral direction from depressions 402. In the preferred embodiment, projections 302 extend approximately three fourths ({fraction (3/4)}) inch in a lateral direction from depressions 402. In another alternative embodiment, unconvoluted thin bases 162, 262 extend laterally in the range of one fourth to three fourths ({fraction (1/4)}-{fraction (3/4)}) inches. Preferably, unconvoluted thin bases 162, 262 extend approximately one half ({fraction (1/2)}) inch in the laterally.